About the author:

China Railway Construction Urban Construction & Transportation Development Co., Ltd.,Suzhou, Jiangsu 215151,China

Abstract:

Based on the Jusong Specially Long-span Bridge, considering the structural characteristics of along-span flexible double-tower double-cable-plane hybrid composite girder cable-stayed bridge, a three-dimensional finite element model was established using ABAQUS, and nonlinear static analysis and modalanalysis were conducted to investigate the stress and deformation characteristics of the bridge deck, staycables, and bridge towers under dead load and highway-class I vehicular load. The results show that thestay cable forces in the main span are significantly higher than those in the side spans, and the cableforce distribution should consider both mid-span deflection control and the balance of horizontaldisplacement at the tower tops. The bridge towers are mainly subjected to axial compression withadditional bending moments, exhibiting the characteristics of compression-bending members. Stressconcentration occurs in the bridge deck at the connection region with the approach bridge,where themaximum tensile stress is approximately 41MPa, and it is recommended to enhance reinforcement in thetensile zones or to provide a gentle-slope transition layer to improve the stress gradient. The fundamentalnatural frequency of the bridge structure is 0.205Hz, and the 10th-order natural frequency is 0.668Hz,with a dense overall frequency distribution and pronounced mode coupling, indicating typical dynamiccharacteristics of long-span flexible structures.